A brain region in mice and patients that is vulnerable to abnormal proteins found in dementia is identified in a study published online this week in Nature Neuroscience.
Aging is accompanied by reduced mental function that often deteriorates into full dementia, such as in Alzheimer’s disease. Abnormalities in amyloid and tau proteins are found in the brains of patients with Alzheimer’s disease; the accumulation of these proteins in regions of the medial temporal lobe is associated with memory impairments in patients such as an inability to remember a list of words.
Scott Small, Karen Duff and colleagues used brain imaging in patients and mouse models to show that the lateral entorhinal cortex, a region in the medial temporal lobe, is particularly vulnerable to dementia processes. They found that people who were later diagnosed with Alzheimer’s had reduced metabolic activity in this brain region and that this is associated with declining memory function. Mutant mice that expressed abnormal tau and amyloid human proteins in this region also showed reduced metabolic activity in their lateral entorhinal cortex that worsened with age.
These results suggest that the lateral entorhinal cortex is an anatomical hub that is particularly vulnerable in dementia and that Alzheimer’s disease related brain dysfunction in particular can then spread from this hub.